Pressurized and filtered
xerographic system

ABSTRACT

AN ELECTROSTATOGRAPHIC COPYING SYSTEM IS CONTAINED WITHIN THE AIR ENCLOSURE WHICH IS SLIGHTLY POSITIVELY AIR PRESSURIZED RELATIVE TO ITS AMBIENT SURROUNDINGS TO REDUCE BOTH INTERNAL AND EXTERNAL CONTAMINATION OF SYSTEM COMPONENTS AND PROVIDE A CONTROLLED INTERNAL AIR FLOW PATTERN. A BLOWER BLOWS AIR INTO THE MACHINE ENCLOSURE THROUGH A FILTER WHICH FILTERS CONTAMINANTS WHICH WOULD OTHERWISE CONTRIBUTE TO PHOTORECEPTOR IMAGE DELETIONS. A SEPARATE OPTICS SYSTEM ENCLOSURE CAN BE INDIRECTLY PRESSURIZED INSIDE THE MAIN ENCLOSURE. AN AIR SHIELD IS POSITIONED TO PREVENT THE INTERNAL AIR FLOW FROM CAUSING CONTAMINATIONS SUCH AS FUMES FROM THE FUSER FROM STRIKING THE PHOTORECEPTOR. THE AIR IS PREFERABLY EXHAUSTED THROUGH THE COPY SHEET EXIT AT THE OPPOSITE SIDE OF THE ENCLOSURE, AND THROUGH THE VACUUM SHEET PICK-OFF SYSTEM. INTERNAL PRESSURE OF LESS THAN 0.1 INCH OF WATER SUSTAINED BY ABOUT 20 CFM IS APPROPRIATE. AMINE CONTAMINATS CAUSING SELENIUM ALLOY PHOTORECEPTOR IMAGE DELATIONS ARE REMOVED BY FILTER MATERIALS SUCH AS ACTIVATED CHARCOAL OR HOPCALITE.

UNITED STATES PATENT AND TRADEMARK OFFICE Published at the request of the applicant or owner in accorfience with the Notice of Dec. 16, 1969, 869 0.4 68?. The abstracts of Defensive Publication applications are identified by rliscinctly numbered series and are arranged chronologically. The heading of each abstract indicates the number of pages 02 specification, including claims and sheets of drawings contained in the application as originally filed. The files of these applications-ere available to the public for inspection and. reproduction may he purchased for 30 cents a sheet.

Defensive Publication applications have not been examinerl as to the merits of alleged. invention. The Patent and Trademark Oflice makes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED NOVEMBER 4, 1975 9&0 (1G. 12

russsrnerzisn AND xsiroousriric overuse Joli-u E. Reclaim; Webster, N 31., essignor to Xerox filoruoretiou, Stamford, Court. Filed 3mm 25, E974, her. No. $33,346 But. Cl. 693g 15/00 US. Cl. 35%3 l heet Drawing. ll Pages Specification An electrostatographic copying system is contained within an air enclosure which is slightly positively air pressurized relative to its ambient surroundings to reduce both internal and external contamination of system components and provide a controlled internal air flow pattern. A blower blows air into the machine enclosure through a filter which filters contaminants which would otherwise contribute to photoreceptor image deletions. A separate optics system enclosure can. be indirectly pressurized inside the main enclosure. An air shield is positioned to prevent the internal air fiow from causing contaminents such as fumes from the fuscr from striking the photoreceptor. The air is preferably exhausted through the copy sheet exit at the oeposite side of the enclosure, and through the vacuum sheet pick-off system. Internal pressure of less than 0.1 inch of water sustained by about 20 cfrn is appropriate. Amine contaminants causing selenium alloy photoreceptor image deletions are removed by filter materials such as activated charcoal or Hopcalite.

0V 4, 1975 I. c. RODOA "WQQJQZZ PRESSURIZED AND FELTERJED XEROGRAPHHC SYSTEM Original Filed June 26, 1974 

